#/usr/bin/python3
i = 1
while i <=3:
    username1 = input("请输入你的用户名，以回车结束：")
    password1 = input("请输入你的密码，以回车结束：")
    if (username1 == 'adu' and  password1 == '123456'):
        print('登录成功：')
        break
    elif (username1 == '' or password1 == ''):
        print('用户名或者密码不为空：')
        i += 1
        continue
    else:
        print('用户名或密码错误，你还剩余{}次机会'.format(3-i))
        i += 1
else:
    print('登陆失败，登录次数已超过3次')
# good